Damage to a vertebral bone, often due to a traumatic fracture or due to invasion of the bone by tumor, at times requires removal of the vertebral body. This operation is known as a corpectomy. Following corpectomy, the resultant gap is generally filled in by a weight bearing support know as a Vertebral Body Replacement (VBR). This helps to restore and maintain the proper spacing between the adjacent bones, and often provides an area for placing graft material to span the adjacent bones in order to allow a fusion to take place.
VBRs may be sized to fit the gap, or be expandable over a range. The expandable VBRs currently available have significant limitations. These include the inability to adequately pack graft material in the channel within them post-expansion, a lack of a satisfactory match of the top and bottom of the implant to the adjacent bone surfaces, and expansion mechanisms that are complex, or take an inordinate amount of time to actuate. A need remains for an implant and surgical technique that will overcome these shortfalls.